Pharmacological stimulation of Wnt/beta-catenin signaling pathway attenuates the course of thioacetamide-induced acute liver failure

Acute liver failure (ALF) is known for extremely high mortality rate, the result of widespread damage of hepatocytes. Orthotopic liver transplantation is the only effective therapy but its application is limited by the scarcity of donor organs. Given the importance in the liver biology of Wnt/beta-catenin signaling pathway, we hypothesized that its stimulation could enhance hepatocyte regeneration and attenuate the course of thioacetamide (TAA)-induced ALF in Lewis rats. Chronic treatment with Wnt agonist was started either immediately after hepatotoxic insult ("early treatment") or when signs of ALF had developed ("late treatment"). Only 23 % of untreated Lewis rats survived till the end of experiment. They showed marked increases in plasma alanine aminotransferase (ALT) activity and bilirubin and ammonia (NH3) levels; plasma albumin decreased significantly. "Early" and "late" Wnt agonist treatment raised the final survival rate to 69 % and 63 %, respectively, and normalized ALT, NH3, bilirubin and albumin levels. In conclusion, the results show that treatment with Wnt agonist attenuates the course of TAA-induced ALF in Lewis rats, both with treatment initiated immediately after hepatotoxic insult and in the phase when ALF has already developed. Thus, the pharmacological stimulation of Wnt/beta-catenin signaling pathway can present a new approach to ALF treatment.

Renoprotection Provided by Additional Diuretic Treatment in Partially Nephrectomized Ren-2 Transgenic Rats Subjected to the Combined RAS and ETA Blockade

Objective

Our previous study in heterozygous Ren-2 transgenic rats (TGR) demonstrated that long-term treatment with endothelin receptor A (ET_A) blocker atrasentan added to the renin-angiotensin system (RAS) blockade had renoprotective effects in a model of chronic kidney disease (CKD) induced by partial nephrectomy. Since ET_A blockade is known to cause edema, we were interested whether diuretic treatment added to this therapy would be beneficial.

Design and Methods

Partial nephrectomy (NX) was performed at the age of 3 months in TGR rats which were subjected to: (i) RAS blockade alone (angiotensin receptor blocker losartan and angiotensin converting enzyme inhibitor trandolapril), (ii) combined RAS (losartan and trandolapril) and ET_A receptor blockade (atrasentan), or (iii) diuretic (hydrochlorothiazide) added to the combined RAS + ET_A blockade for 50 weeks following NX.

Results

At the end of the study systolic blood pressure and cardiac hypertrophy were similarly decreased in all treated groups. Survival was significantly improved by ET_A receptor blockade added to RAS blockade with no further effects of diuretic treatment. However, additional diuretic treatment combined with RAS + ET_A blockade decreased body weight and had beneficial renoprotective effects - reductions of both kidney weight and kidney damage markers. Proteinuria gradually increased in rats treated with RAS blockade alone, while it was substantially lowered by additional ET_A blockade. In rats treated with additional diuretic, proteinuria was progressively reduced throughout the experiment.

Conclusion

A diuretic added to the combined RAS and ET_A blockade has late renoprotective effects in CKD induced by partial nephrectomy in Ren-2 transgenic rats. The diuretic improved: renal function (evaluated as proteinuria and creatinine clearance), renal morphology (kidney mass, glomerular volume), and histological markers of kidney damage (glomerulosclerosis index, tubulointerstitial injury).

Epoxyeicosatrienoic Acid-Based Therapy Attenuates the Progression of Postischemic Heart Failure in Normotensive Sprague-Dawley but Not in Hypertensive Ren-2 Transgenic Rats

Epoxyeicosatrienoic acids (EETs) and their analogs have been identified as potent antihypertensive compounds with cardio- and renoprotective actions. Here, we examined the effect of EET-A, an orally active EET analog, and c-AUCB, an inhibitor of the EETs degrading enzyme soluble epoxide hydrolase, on the progression of post-myocardial infarction (MI) heart failure (HF) in normotensive Hannover Sprague-Dawley (HanSD) and in heterozygous Ren-2 transgenic rats (TGR) with angiotensin II-dependent hypertension. Adult male rats (12 weeks old) were subjected to 60-min left anterior descending (LAD) coronary artery occlusion or sham (non-MI) operation. Animals were treated with EET-A and c-AUCB (10 and 1 mg/kg/day, respectively) in drinking water, given alone or combined for 5 weeks starting 24 h after MI induction. Left ventricle (LV) function and geometry were assessed by echocardiography before MI and during the progression of HF. At the end of the study, LV function was determined by catheterization and tissue samples were collected. Ischemic mortality due to the incidence of sustained ventricular fibrillation was significantly higher in TGR than in HanSD rats (35.4 and 17.7%, respectively). MI-induced HF markedly increased LV end-diastolic pressure (P_ed) and reduced fractional shortening (FS) and the peak rate of pressure development [+(dP/dt)_max] in untreated HanSD compared to sham (non-MI) group [P_ed: 30.5 ± 3.3 vs. 9.7 ± 1.3 mmHg; FS: 11.1 ± 1.0 vs. 40.8 ± 0.5%; +(dP/dt)_max: 3890 ± 291 vs. 5947 ± 309 mmHg/s]. EET-A and c-AUCB, given alone, tended to improve LV function parameters in HanSD rats. Their combination amplified the cardioprotective effect of single therapy and reached significant differences compared to untreated HanSD controls [P_ed: 19.4 ± 2.2 mmHg; FS: 14.9 ± 1.0%; +(dP/dt)_max: 5278 ± 255 mmHg/s]. In TGR, MI resulted in the impairment of LV function like HanSD rats. All treatments reduced the increased level of albuminuria in TGR compared to untreated MI group, but neither single nor combined EET-based therapy improved LV function. Our results indicate that EET-based therapy attenuates the progression of post-MI HF in HanSD, but not in TGR, even though they exhibited renoprotective action in TGR hypertensive rats.

Renoprotective effects of ET(A) receptor antagonists therapy in experimental non-diabetic chronic kidney disease: Is there still hope for the future?

Chronic kidney disease (CKD) is a life-threatening disease arising as a frequent complication of diabetes, obesity and hypertension. Since it is typically undetected for long periods, it often progresses to end-stage renal disease. CKD is characterized by the development of progressive glomerulosclerosis, interstitial fibrosis and tubular atrophy along with a decreased glomerular filtration rate. This is associated with podocyte injury and a progressive rise in proteinuria. As endothelin-1 (ET-1) through the activation of endothelin receptor type A (ET(A)) promotes renal cell injury, inflammation, and fibrosis which finally lead to proteinuria, it is not surprising that ET(A) receptors antagonists have been proven to have beneficial renoprotective effects in both experimental and clinical studies in diabetic and non-diabetic CKD. Unfortunately, fluid retention encountered in large clinical trials in diabetic CKD led to the termination of these studies. Therefore, several advances, including the synthesis of new antagonists with enhanced pharmacological activity, the use of lower doses of ET antagonists, the addition of diuretics, plus simply searching for distinct pathological states to be treated, are promising targets for future experimental studies. In support of these approaches, our group demonstrated in adult subtotally nephrectomized Ren-2 transgenic rats that the addition of a diuretic on top of renin-angiotensin and ET(A) blockade led to a further decrease of proteinuria. This effect was independent of blood pressure which was normalized in all treated groups. Recent data in non-diabetic CKD, therefore, indicate a new potential for ET(A) antagonists, at least under certain pathological conditions.

Overexpression of TET dioxygenases in seminomas associates with low levels of DNA methylation and hydroxymethylation

Germ cell tumors and particularly seminomas reflect the epigenomic features of their parental primordial germ cells (PGCs), including genomic DNA hypomethylation and expression of pluripotent cell markers. Because the DNA hypomethylation might be a result of TET dioxygenase activity, we examined expression of TET1-3 enzymes and the level of their product, 5-hydroxymethylcytosine (5hmC), in a panel of histologically characterized seminomas and non-seminomatous germ cell tumors. Expression of TET dioxygenase mRNAs was quantified by real-time PCR. TET1 expression and the level of 5hmC were examined immunohistochemically. Quantitative assessment of 5-methylcytosine (5mC) and 5hmC levels was done by the liquid chromatography-mass spectroscopy technique. We found highly increased expression of TET1 dioxygenase in most seminomas and strong TET1 staining in seminoma cells. Isocitrate dehydrogenase 1 and 2 mutations were not detected, suggesting the enzymatic activity of TET1. The levels of 5mC and 5hmC in seminomas were found decreased in comparison to non-seminomatous germ cell tumors and healthy testicular tissue. We propose that TET1 expression should be studied as a potential marker of seminomas and mixed germ cell tumors and we suggest that elevated expression of TET dioxygenase enzymes is associated with the maintenance of low DNA methylation levels in seminomas. This "anti-methylator" phenotype of seminomas is in contrast to the CpG island methylator phenotype (CIMP) observed in a fraction of tumors of various types.

DNA hypomethylation and aberrant expression of the human endogenous retrovirus ERVWE1/syncytin-1 in seminomas

BACKGROUND

Syncytin-1 and 2, human fusogenic glycoproteins encoded by the env genes of the endogenous retroviral loci ERVWE1 and ERVFRDE1, respectively, contribute to the differentiation of multinucleated syncytiotrophoblast in chorionic villi. In non-trophoblastic cells, however, the expression of syncytins has to be suppressed to avoid potential pathogenic effects. Previously, we have shown that the transcriptional suppression of ERVWE1 promoter is controlled epigenetically by DNA methylation and chromatin modifications. In this study, we describe the aberrant expression of syncytin-1 in biopsies of testicular germ cell tumors.

RESULTS

We found efficient expression and splicing of syncytin-1 in seminomas and mixed germ cell tumors with seminoma component. Although another fusogenic gene, syncytin-2 was also derepressed in seminomas, its expression was significantly lower than that of syncytin-1. Neither the transcription factor GCM1 nor the increased copy number of ERVWE1 were sufficient for this aberrant expression of syncytin-1 in seminomas. In accordance with our recent finding of the highly increased expression of TET1 dioxygenase in most seminomas, the ERVWE1 promoter was significantly hypomethylated in comparison with the matched controls. In contrast, 5-hydroxymethylcytosine levels were not detectable at the ERVWE1 promoter. We further describe that another endogenous retroviral element adjacent to ERVWE1 remains transcriptionally suppressed and two additional HERV-W family members are only slightly upregulated in seminomas.

CONCLUSIONS

We conclude that DNA demethylation of the ERVWE1 promoter in seminomas is a prerequisite for syncytin-1 derepression. We propose the spliced syncytin-1 expression as a marker of seminoma and suggest that aberrant expression of endogenous retroviruses might be a correlate of the hypomethylated genome of seminomas.

Orally active epoxyeicosatrienoic acid analog does not exhibit antihypertensive and reno- or cardioprotective actions in two-kidney, one-clip Goldblatt hypertensive rats

This study examined the effects of a novel orally active 14,15-epoxyeicosatrienoic acid analog (EET-A) on blood pressure (BP) and myocardial infarct size (IS) in two-kidney, one-clip (2K1C) Goldblatt hypertensive rats during sustained phase of hypertension. Between days 31 and 35 after clip placement the rats were treated with EET-A and BP was monitored by radiotelemetry; sham-operated normotensive rats were used as controls. Tissue concentrations of epoxyeicosatrienoic acids served as a marker of production of epoxygenase metabolites. The rats were subjected to acute myocardial ischemia/reperfusion (I/R) injury and IS was determined. We found that EET-A treatment did not lower BP in 2K1C rats and did not alter availability of biologically active epoxygenase metabolites in 2K1C or in sham-operated rats. The myocardial IS was significantly smaller in untreated 2K1C rats as compared with normotensive controls and EET-A reduced it in controls but not in 2K1C rats. Our findings suggest that during the phase of sustained hypertension 2K1C Goldblatt hypertensive rats exhibit increased cardiac tolerance to I/R injury as compared with normotensive controls, and that in this animal model of human renovascular hypertension short-term treatment with EET-A does not induce any antihypertensive and cardioprotective actions.

Pro-inflammatory effects of interleukin-35 in rheumatoid arthritis

OBJECTIVE

Interleukin-35 (IL-35) is a heterodimeric member of the IL-12 family consisting of p35/IL-12a and EBI3/IL-27b subunits. Expressed in murine Treg cells, IL-35 controls inflammatory diseases in mouse models. However, human IL-35 is expressed in Teff cells rather than in Treg cells and is shown to be upregulated under inflammatory conditions. Our aim was to examine the involvement of IL-35 in the pathogenesis of rheumatoid arthritis (RA).

METHODS

Immunohistochemical and immunofluorescence analysis was used to determine the expression and localization of IL-35 and its subunits (p35/EBI3) and IL-35 receptor (IL12Rβ2/gp130) in RA, osteoarthritis (OA) and psoriatic arthritis (PsA) synovial tissues. Expression of p35/EBI3 subunits and release of inflammatory cytokines upon stimulation with IL-35 were assessed in RA synovial fibroblasts (SFs) and peripheral blood mononuclear cells (PBMCs).

RESULTS

Both IL-35 and its subunits were upregulated in RA in comparison with OA or PsA synovium. Using cell-specific markers, p35 and EBI3 were identified in macrophages, dendritic cells, SFs, and T as well as B cells in RA synovium. Both p35 and EBI3 were induced by TNFα in RASFs and PBMCs. IL-35 dose-dependently upregulated release of pro-inflammatory mediators IL-1β, IL-6 and MCP-1 in PBMCs. While gp130 receptor subunit was upregulated in RA synovium and was expressed in RASFs and PBMCs, there was no difference in IL12Rβ2 expression subunit among tissues and its presence in RASFs was lacking.

CONCLUSION

Upregulation of IL-35 at sites of inflammation in RA and its pro-inflammatory potential suggests that IL-35 might play an important role in RA pathogenesis.

[Extramammary Paget´s disease of the vulva - a case report]

OBJECTIVE

Analysis of one case of vulvar extramammary Paget´s disease (EMPD) and associated well differentiated endometrial adenocarcinoma.Desing: A case report.

METHODS AND RESULTS

On this case report we present current theoretical knowledge about EMPD, difficulty of diagnostics, treatment and dispensarization the patients with this rare intraepithelial non-squamous neoplasia. We report a rare case of a 62 years old female patient with extramammary Paget´s disease of vulva and associated well differentiated endometrial adenocarcinoma.

CONCLUSIONS

EMPD is a rare intraephitelial non-squamous neoplasia, which represents less then 1% vulvar tumors. Predominantly it affects white women between 60 and 80 years of age. EMPD occurs in cutaneous areas bearing apocrine glands - vulva, perineum, perianal area, axilla, penis, scrotum and rarely region of tights or buttocks. It is characterized microscopically by the presence of specific tumor cells called Paget´s cells - atypical large cells with pale clear cytoplasm and large round nuclei.

KEYWORDS

extramammary Paget´s disease, EMPD, Paget´s cells, vulvectomy, imiquimod 5%, photodynamic therapy, imunotherapy, radiotherapy.

Addition of ET(A) receptor blockade increases renoprotection provided by renin-angiotensin system blockade in 5/6 nephrectomized Ren-2 transgenic rats

AIMS

There is evidence that in addition to hypertension and hyperactivity of the renin-angiotensin system (RAS), enhanced intrarenal activity of endothelin (ET) system contributes to the pathophysiology and progression of chronic kidney disease (CKD). This prompted us to examine if this progression would be alleviated by addition of type A ET receptor (ETA) blockade to the standard blockade of RAS.

MAIN METHODS

Ren-2 transgenic rats (TGR) after 5/6 renal ablation (5/6 NX) served as a model of CKD. For RAS inhibition a combination of angiotensin-converting enzyme inhibitor (trandolapril, 6 mg/L drinking water) and angiotensin II type 1 receptor blocker (losartan, 100 mg/L drinking water) was used. Alternatively, ETA receptor blocker (atrasentan, 5 mg·kg(-1)·day(-1) in drinking water) was added to the combined RAS blockade. The follow-up period was 44 weeks after 5/6 NX, and the rats' survival rate, systolic blood pressure (SBP), proteinuria and indices of renal glomerular damage were evaluated.

KEY FINDINGS

The survival rate was at first improved, by either therapeutic regime, however, the efficiency of RAS blockade alone considerably decreased 36 weeks after 5/6 NX: final survival rate of 65% was significantly lower than 91% achieved with combined RAS and ETA receptor blockade. SBP was not affected by the addition of ETA blockade while proteinuria and renal glomerular damage were further reduced.

SIGNIFICANCE

Our data show that a combined RAS and ETA receptor blockade exhibits additional beneficial effects on survival rate and the progression of CKD in 5/6 NX TGR, as compared with RAS inhibition alone.

Soluble epoxide hydrolase inhibition exhibits antihypertensive actions independently of nitric oxide in mice with renovascular hypertension

OBJECTIVE

The present study was performed to examine whether the blood pressure (BP)-lowering effects of soluble epoxide hydrolase (sEH) inhibition in two-kidney, one-clip (2K1C) Goldblatt hypertension are nitric oxide (NO) dependent.

METHODS

Mice lacking the endothelial NO synthase (eNOS) gene (eNOS-/-) and their wild-type controls (eNOS+/+) underwent clipping of one renal artery. BP was monitored by radiotelemetry and the treatment with the sEH inhibitor cis-4-[4-(3-adamantan-1-yl-ureido)cyclohex-yloxy]-benzoic acid (c-AUCB) was initiated on day 25 after clipping and lasted for 14 days. Renal concentrations of epoxyeicosatrienoic acids (EETs) and their inactive metabolite dihydroxyeicosatrienoic acids (DHETs) were measured in the nonclipped kidney. Renal NO synthase (NOS) activity was determined by measuring the rate of formation of L-[(14)C]citruline from L-[(14)C]arginine.

RESULTS

Treatment with the sEH inhibitor elicited similar BP decreases that were associated with increases in daily sodium excretion in 2K1C eNOS+/+ as well as 2K1C eNOS-/- mice. In addition, treatment with the sEH inhibitor increased the ratio of EETs/DHETs in the nonclipped kidney of 2K1C eNOS+/+ as well as 2K1C eNOS-/- mice. Treatment with the sEH inhibitor did not alter renal NOS activity in any of the experimental groups.

CONCLUSIONS

Collectively, our present data suggest that the BP-lowering effects of chronic sEH inhibition in 2K1C mice are mainly associated with normalization of the reduced availability of biologically active EETs in the nonclipped kidney and their direct natriuretic actions.

[Risk factors for recurrent disease in borderline ovarian tumors]

OBJECTIVE

To evaluate risk factors for development of recurrent disease in borderline ovarian tumors.

DESIGN

Retrospective study of 10-years single institution population.

SETTING

Dept. of Gynecology and Obstetrics, 3rd Medical Faculty of Charles University in Prague.

METHOD

59 consecutive cases of borderline ovarian tumors (BOT) were analyzed for age, histopathological type, DNA ploidy, stage, presence of invasive and non-invasive peritoneal implants, type of surgical procedure, residual disease, adjuvant therapy, recurrence and long-time prognosis of the patients.

RESULTS

Median follow-up was 47 months (range 1-144). There were 5 (8.5%) patients with DNA aneuploid tumors in the study group; 4 of them were younger than 50 years, 4 of them were early stage serous BOT; no one recur so far. No death of disease was described in the whole study group; only 2 patients (3.4%) developed recurrent disease - both were young patients after conservative surgery for serous diploid stage I/II BOT. Conservative surgery was the only significant factor for recurrence in univariate analysis (p = 0.0159) in our setting.

CONCLUSION

DNA ploidy was not proved to be prognostic factor in borderline ovarian tumors in our study group. The only significant risk factor for development of recurrent disease was conservative surgery, with no influence on overall survival.

Epigenetic regulation of transcription and splicing of syncytins, fusogenic glycoproteins of retroviral origin

Syncytin-1 and -2, human fusogenic glycoproteins encoded by the env genes of the endogenous retroviral loci ERVWE1 and ERVFRDE1, respectively, contribute to the differentiation of multinucleated syncytiotrophoblast in chorionic villi. In non-trophoblastic cells, however, the expression of syncytins has to be suppressed to avoid potential pathogenic effects. We studied the epigenetic suppression of ERVWE1 and ERVFRDE1 5′-long terminal repeats by DNA methylation and chromatin modifications. Immunoprecipitation of the provirus-associated chromatin revealed the H3K9 trimethylation at transcriptionally inactivated syncytins in HeLa cells. qRT-PCR analysis of non-spliced ERVWE1 and ERVFRDE1 mRNAs and respective env mRNAs detected efficient splicing of endogenously expressed RNAs in trophoblastic but not in non-placental cells. Pointing to the pathogenic potential of aberrantly expressed syncytin-1, we have found deregulation of transcription and splicing of the ERVWE1 in biopsies of testicular seminomas. Finally, ectopic expression experiments suggest the importance of proper chromatin context for the ERVWE1 splicing. Our results thus demonstrate that cell-specific retroviral splicing represents an additional epigenetic level controling the expression of endogenous retroviruses.

[Guideline for treatment of gynaecological malignant tumours 2010---endometrial carcinoma]

OBJECTIVE

To develop guideline for primary surgical treatment of endometrial carcinoma.

DESIGN

Review, consensus of expert group.

SETTING

Dept. of Gynaecology and Obstetrics, 3rd Medical Faculty of Charles University in Prague.

METHOD

A retrospective review of published data, analysis of statistic data from Czech Republic, consensus among proposers and opponents.

RESULTS

The guideline recognizes endometrial carcinoma patients based on their risk and recommends type of surgical treatment for certain group. It emphasizes the importance of centralized oncogynaecological treatment. Surgical staging remains the basic principle for treatment of endometrial carcinoma patients. The aim of pre-operative diagnostics is to estimate the extent of the disease--"interim staging", that can be different from definitive histopathological staging. Based on risk factors patients are divided into low or high risk group. Standard procedure for low risk patients is hysterectomy and bilateral salpingoophorectomy. It is advisable to use peroperative biopsy in these patients that can shift the patient to high risk group. High risk patients are recommended for hysterectomy, bilateral salpingoophorectomy, and systematic aortopelvic lymphadenectomy. The guideline contains recommendation for young patients wishing to preserve their fertility, for cases of inadequate surgery and for follow-up.

CONCLUSION

Guideline for treatment of endometrial carcinoma is recommendation for clinicians and other subjects who participate on the process of the diagnostics/treatment of endometrial carcinoma patients. All points of the guideline were discussed and voted about by all participants of expert group.

[Post-traumatic pseudocyst of the spleen]

INTRODUCTION

Post-traumatic splenic pseudocysts are rare condition and comprise more than 75% of non-parasitic cysts. They result from subcapsular or intraparenchymatous hematoma, by its liquefaction and creation of the fibrous peripheral capsula. Splenic pseudocysts have no epithelial lining, its diameter could be more than 15 cm and are mostly symptomatic.

CASE REPORT

A female, 53 years old, was admitted to the Clinic of surgery with blunt pains in the left hypochondrium after falling on the left side of body 6 months ago. Ultrasonography and CT scan reveal posttraumatic pseudocyst of the spleen, 156 x 135 x 148 mm in diameter. The splenic parenchyma was reduced to 15 mm dorso-caudal. Extirpation of the pseudocyst and splenectomy during laparotomy was performed with healing per primam. The patient was discharged 6 day after surgery.

CONCLUSION

Posttraumatic splenic pseudocysts are good diagnosed in CT scan. Giant pseudocysts and psuedocysts in splenic hilus require surgical resection. Spleen parenchyma preserving operations, currently recommended in small cysts, reduce the risk of early and late septic complications, particularly overwhelming postsplenectomy sepsis. Partial splenectomy offers a definitive treatment of a splenic cyst while preserving splenic functions. Miniinvasive surgery as a percutaneous drainage and laparoscopic fenestration have an unacceptably high rate of failure.

Persistent antihypertensive effect of aliskiren is accompanied by reduced proteinuria and normalization of glomerular area in Ren-2 transgenic rats

The effects of the human renin inhibitor aliskiren on blood pressure (BP), end-organ damage, proteinuria, and tissue and plasma angiotensin (ANG) II levels in young and adult heterozygous Ren-2 transgenic rats (TGR) were evaluated and compared with the effect of the ANG type 1 (AT(1)) receptor blocker losartan during treatment and after 12 days after the withdrawal of drug treatments. BP was monitored by telemetry from the age of 32 days on (young rats) and at 100 days (adult rats). Aliskiren (10 mg·kg(-1)·day(-1) in osmotic minipumps) or losartan (5 mg·kg(-1)·day(-1) in drinking water) treatment was applied for 28 days in young rats and for 70 days in adult rats. In young untreated TGR, severe hypertension rapidly evolved. Adult untreated TGR exhibited stable established hypertension. Both aliskiren and losartan fully prevented the development of hypertension and cardiac hypertrophy in young TGR and normalized BP and cardiac hypertrophy in adult TGR. After cessation of aliskiren treatment in both young and adult TGR BP and cardiac hypertrophy were persistently reduced, while after losartan withdrawal BP and cardiac hypertrophy rapidly increased. In adult aliskiren-treated rats proteinuria was significantly reduced compared with losartan (the effect persisting after withdrawal of treatment), and this decrease strongly correlated with normalization of glomerular size in these animals. In conclusion, aliskiren and losartan had similar antihypertensive effects during chronic treatment, but the antihypertensive and organoprotective effects of aliskiren were persistent even after the 12-day washout period. The durable effect on proteinuria can possibly be attributed to the normalization of glomerular morphology.

End-organ damage in hypertensive transgenic Ren-2 rats: influence of early and late endothelin receptor blockade

The rat strain transgenic for the murine Ren-2 renin gene (TGR) is defined as a monogenic model of angiotensin II-dependent hypertension with endogenous activation of the renin-angiotensin system. Homozygous males TGR develop malignant hypertension with a strong salt-sensitive component. These animals show severe hypertension, proteinuria and high mortality. Morphological changes of renal parenchyma correspond to chronic ischemic glomerular changes. Heterozygous TGR develop only mild hypertension and thus provide a more suitable model of hypertension regarding to clinical studies. Within the renal parenchyma, secondary focal segmental glomerulosclerosis (FSGS) predominates. High-salt diet in heterozygous animals induces transition from benign to malignant phase of hypertension. In this case, ischemic glomerular changes are superimposed on preexisting secondary FSGS. In the regression model of hypertension (late-onset treatment) the effect of salt intake is attenuated. In homozygous TGR, early selective ET(A) receptor blockade decreased blood pressure and ameliorated end-organ damage. Late selective ET(A) receptor blockade reduced podocyte injury despite final severe hypertension. Survival rate was markedly improved in both regimens with ET(A) selective blockade, while there was only partial improvement with early non-selective blockade. Both bosentan and atrasentan decreased ET-1 levels in both regimens. In heterozygous TGR, early and late ET(A) treatment substantially while ET(A)/ET(B) treatment partially improved survival rate. Significant effect on BP was found with early and late ET(A) blockade, while ET(A)/ET(B) blockade had no effect. Bosentan and atrasentan similarly decreased ET-1 levels on both regimens. In conclusion, selective ET(A) receptor blockade is superior to nonselective ET(A)/ET(B) receptor blockade in attenuating hypertension and end-organ damage. Its effect is more pronounced when applied early in the life.

[5/6 nephrectomy as an experimental model of chronic renal failure and adaptation to reduced nephron number]

Experimental model of 5/6 nephrectomy or the remnant kidney model represents one of the most used animal models of progressive renal failure by reduced nephron number, best-characterized in rats. The reduction of renal mass is achieved by either infarction or surgical excision of both poles, with removal of the contralateral kidney. It enables to investigate the influence of pharmacological, nutritive and other factors on functional and morphological renal parameters. 5/6 nephrectomy produced by infarction is characterised by high plasma renin levels. By contrast, reduction of an equivalent amount of renal parenchyma by surgical excision does not result in the development of hypertension and plasma renin activity is normal to low. The initially normal remnant nephrons undergo compensatory functional and structural adaptations. Simultaneous glomerular hypertension is one of the main factors responsible for the development of renal injury. Morphologicaly progressive focal segmental to global glomerulosclerosis is present, accompanied clinically by increasing proteinuria and deteriorating renal function.

Adiponectin as a potential marker of prostate cancer progression: studies in organ-confined and locally advanced prostate cancer

Serum levels of adiponectin were measured in patients with benign prostatic hyperplasia and prostate cancer of pT2 and pT3 stage. Adiponectin ELISA assay, immunohistochemistry, and selected metabolic and biochemical parameters measurement was performed in 25 patients with benign prostatic hyperplasia and 43 with prostate cancer (17 patients with organ-confined and 26 patients with locally advanced disease). Serum adiponectin levels did not differ between prostate benign hyperplasia and cancer clinical stage T2, but was significantly higher in pT3 relative to pT2 group (14.51+/-4.92 vs. 21.41+/-8.12, P = 0.003). Tissue immunohistochemistry showed enhanced staining in neoplastic prostate glands and intraepithelial neoplasia relative to benign prostatic hyperplasia without distinction between disease grade and stage. Serum adiponectin levels are higher in locally advanced relative to organ-confined prostate cancer and may thus serve as an auxiliary marker providing further improvement for discrimination between pT2 and pT3 stages.

Differences in pathogenicity among strains of the same or different avian leukosis virus subgroups

An efficient induction of wasting disease in chickens by avian leukosis virus (ALV), particularly ALV subgroup C, requires >102 infectious units virus inoculated in mid embryogenesis. The most conspicuous symptoms of the disease were induced by ALV subgroup C; however, significant differences in the occurrence of wasting disease were found among individual members of this subgroup. Almost comparable pathogenicity was exhibited by ALV subgroup D, whereas viruses of subgroups B and A proved to be moderately and almost non-pathogenic, respectively. Using antibodies to cellular antigens, tissue alterations were shown clearly in ALV-C-infected chickens. An essential feature was depletion of lymphocytes in the thymus, bursa and spleen. While the number of dendritic cells in the bursa was increased, their representation in the thymus and spleen was reduced. In the spleen, however, the reduction of dendritic cells concerned only an ellipsoid compartment, which in itself was also markedly reduced. An increased number of macrophages in the thymus and spleen corresponded with the observed general activation of the monocyte-macrophage system. In the spleen, CD4+ T cells were reduced while CD8+ T cells were increased. In agreement with this finding was a failure of chickens to respond to Brucella antigen and an inability of their splenocytes to respond to Concanavalin A, both of which pointed to the damage of immune reactivity. Variation in the pathogenicity among individual ALV strains provides ground for depicting gene sequences playing an important role in ALV acute pathogenicity.

An unusual cause of renal amyloidosis secondary to gout: the first description of familial occurrence

BACKGROUND

AA amyloidosis caused by the chronic inflammation accompanying gouty arthritis is extremely rare and familial occurrence has not been described so far.

CASE REPORT

We present the case of two brothers (47 and 44 years old) with 7- and 10-year history of hyperuricaemia and chronic tophaceous gout with polyarticular involvement. The enzymatic assay performed in their erythrocytes proved the partial hypoxanthine-guanine phosphoribosyl transferase deficiency (Kelley-Seegmiller syndrome), the genetic defect of purine metabolism. Later on they developed proteinuria and chronic renal insufficiency /CRI/. Renal biopsy disclosed the combination of AA amyloidosis and gouty nephropathy in both the cases. Despite the standard treatment the older brother progressed to chronic renal failure. On the contrary, the younger one being longterm treated with oral colchicin have stabilized CRI.

CONCLUSIONS

Only several cases of AA renal amyloidosis until recently, secondary to gout have been reported. Our case represents the first report of familial occurrence of this extremely rare disease.

[Morphological characteristic of renal injury in hypertensive rat strain transgenic for the mouse Ren-2 renin gene (TGR [mRen2] 27]

The hypertensive rat strain transgenic for the mouse Ren-2 renin gene (TGR) strain name TGR [mRen 2] 27 is a valuable monogenic model of renin-dependent and thus angiotensin II dependent hypertension. It carries a salt -sensitive component. Homozygous animals exhibit clinically and morphologically typical sings of fulminant hypertension. Glomerular changes in accelerated (malignant) hypertension are acute or chronic. The acute changes have focal character; the most obvious change is segmental fibrinoid necrosis. Fibrinoid necrosis may extend from a similar lesion in the afferent arteriole and may be associated with crescent. Chronic changes are of two different types. The first is similar to that seen in benign hypertension, in that there is collapse of the capillary tuft with wrinkling of the glomerular basement membrane accompanied by collagenization of Bowmann's space. In the second type, glomeruli are also collapsed but seem almost acellular. Male heterozygous TGR are more suitable for experiments because their hypertension is lower and this model is much more similar to clinical situation. Morphologically prominent hyalinosis and segmental sclerotisation of capillary tuft of some glomeruli is present. These features correspond to secondary form of focal segmental glomerulosclerosis (FSGS). High salt diet in heterozygous animals induces a transition from benign to malignant phase of hypertension. In such case ischemic changes are superimposed on the pre-existing renal parenchymal disease (secondary FSGS). Selective blockade of endothelin receptors ET(A) is superior to non-selective ET(A)/ET(B) blockade in attenuating of hypertension and also morphology. ET receptor blockade in homozygous and heterozygous TGR has similar effect on morphological structure of renal parenchyma applied in rats with established hypertension as in young animals. Podocyte injury is crucial also in experimental hypertensive glomerulopathy. Podocytes showed degenerative changes and thickening of glomerular basement membrane was also present. Degree of morphological podocyte injury rather than hypertension correlated with mortality in homozygous TGR.

Resistin in rheumatoid arthritis synovial tissue, synovial fluid and serum

BACKGROUND

Resistin is a newly identified adipocytokine which has demonstrated links between obesity and insulin resistance in rodents. In humans, proinflammatory properties of resistin are superior to its insulin resistance-inducing effects.

OBJECTIVES

To assess resistin expression in synovial tissues, serum and synovial fluid from patients with rheumatoid arthritis, osteoarthritis and spondylarthropathies (SpA), and to study its relationship with inflammatory status and rheumatoid arthritis disease activity.

METHODS

Resistin expression and localisation in synovial tissue was determined by immunohistochemistry and confocal microscopy. Serum and synovial fluid resistin, leptin, interleukin (IL)1beta, IL6, IL8, tumour necrosis factor alpha, and monocyte chemoattractant protein-1 levels were measured. The clinical activity of patients with rheumatoid arthritis was assessed according to the 28 joint count Disease Activity Score (DAS28).

RESULTS

Resistin was detected in the synovium in both rheumatoid arthritis and osteoarthritis. Staining in the sublining layer was more intensive in patients with rheumatoid arthritis compared with those with osteoarthritis. In rheumatoid arthritis, macrophages (CD68), B lymphocytes (CD20) and plasma cells (CD138) but not T lymphocytes (CD3) showed colocalisation with resistin. Synovial fluid resistin was higher in patients with rheumatoid arthritis than in those with SpA or osteoarthritis (both p<0.001). In patients with rheumatoid arthritis and SpA, serum resistin levels were higher than those with osteoarthritis (p<0.01). Increased serum resistin in patients with rheumatoid arthritis correlated with both CRP (r=0.53, p<0.02), and DAS28 (r=0.44, p<0.05), but not with selected (adipo) cytokines.

CONCLUSION

The upregulated resistin at local sites of inflammation and the link between serum resistin, inflammation and disease activity suggest a role for resistin in the pathogenesis of rheumatoid arthritis.

Late-onset endothelin-A receptor blockade reduces podocyte injury in homozygous Ren-2 rats despite severe hypertension

We have recently found in male homozygous hypertensive Ren-2 transgenic rats (TGRs) fed a high-salt diet that early onset selective endothelin (ET) A (ET(A)) or nonselective ET(A)/ET B (ET(B)) receptor blockade improved survival rate and reduced proteinuria, glomerulosclerosis, and cardiac hypertrophy, whereas selective ET(A) receptor blockade also significantly attenuated the rise in blood pressure. Because antihypertensive therapy in general is known to be more efficient when started at early age, our study was performed to determine whether onset of ET receptor blockade at a later age in animals with established hypertension will have similar protective effects as does early-onset therapy. Male homozygous TGRs and age-matched normotensive Hannover Sprague-Dawley rats were fed a high-salt diet between days 51 and 90 of age. TGRs received vehicle (untreated), the selective ET(A) receptor blocker atrasentan (ABT-627), or the nonselective ET(A)/ET(B) receptor blocker bosentan. Survival rates in untreated and bosentan-treated TGRs were 50% and 64%, respectively, whereas with atrasentan, survival rate of TGR was 96%, thus, similar to 93% in Hannover Sprague-Dawley rats. From day 60 on, systolic blood pressure in atrasentan-treated TGRs was transiently lower (P<0.05) than in untreated or bosentan-treated TGRs. Glomerular podocyte injury was substantially reduced with atrasentan treatment independent of severe hypertension and strongly correlated with survival (P<0.001). Our data indicate that in homozygous TGR ET receptors play an important role also in established hypertension. Selective ET(A) receptor blockade not only reduces podocyte injury and end-organ damage but also improves growth and survival independently of hypertension.

Chronic endothelin receptor blockade reduces end-organ damage independently of blood pressure effects in salt-loaded heterozygous Ren-2 transgenic rats

The present study was performed to evaluate the role of an interaction between the endothelin (ET) and the renin-angiotensin systems (RAS) in the development and maintenance of hypertension and in hypertension-associated end-organ damage in heterozygous male and female transgenic rats harboring the mouse Ren-2 renin gene (TGR). Twenty-eight days old heterozygous TGR and age-matched transgene-negative normotensive Hannover Sprague-Dawley rats (HanSD) were randomly assigned to groups with normal-salt (NS) or high-salt (HS) intake. Nonselective ET(A)/ET(B) receptor blockade was achieved with bosentan (100 mg.kg(-1).day(-1)). All male and female HanSD as well as heterozygous TGR on NS exhibited 100 % survival rate until 180 days of age (end of experiment). HS diet in heterozygous TGR induced a transition from benign to malignant phase hypertension. The survival rates in male and in female heterozygous TGR on the HS diet were 46 % and 80 %, respectively, and were significantly improved by administration of bosentan to 76 % and 97 %, respectively. Treatment with bosentan did not influence either the course of hypertension (measured by plethysmography in conscious animals) or the final levels of blood pressure (measured by a direct method in anesthetized rats) in any of the experimental groups of HanSD or TGR. Administration of bosentan in heterozygous TGR fed the HS diet markedly reduced proteinuria, glomerulosclerosis and attenuated the development of cardiac hypertrophy compared with untreated TGR. Our data show that the ET receptor blockade markedly improves the survival rate and ameliorates end-organ damage in heterozygous TGR exposed to HS diet. These findings indicate that the interaction between the RAS and ET systems plays an important role in the development of hypertension-associated end-organ damage in TGR exposed to salt-loading.

Adipocytokines and cancer

Adipose tissue-produced hormones significantly affect the metabolism of lipids and carbohydrates as well as numerous other processes in human body. It is generally accepted that endocrine dysfunction of adipose tissue may represent one of the causal links between obesity and insulin resistance/diabetes. Epidemiological studies underlined that obesity represents a significant risk factor for the development of cancer, although the exact mechanism of this relationship remains to be determined. Multiple recent studies have indicated that some of adipose tissue-derived hormones may significantly influence the growth and proliferation of tumorous stroma and malignant cells within. Here we review current knowledge about possible relationship of leptin and adiponectin to the etiopathogenesis of different malignant tumors. Most of the studies indicated that while leptin may potentiate the growth of cancer cells in vitro, adiponectin appears to have an opposite effect. Further studies are necessary to decide whether obesity-induced endocrine dysfunction of adipose tissue can directly influence carcinogenesis in different tissues and organs.

[Fibrillary glomerulonephritis--a rare cause of nephrotic syndrome]

Fibrillary glomerulonephritis (FGN) is a rarely diagnosed disease with clinical manifestations such as proteinuria, microscopic hematuria, nephrotic syndrome or decreased kidney function. Around one half of patients develop chronic renal failure in the course of several years. The diagnosis of fibrillary glomerulonephritis is to be established only basing on the results of renal biopsy. Pathognomonic is the electron-microscopic examination, evidencing fibrillar deposits in mesangium and in basal membranes of glomeruli. Fibrils are similar to those seen at amyloidosis, however, with larger diameter, non-linear deposition and do not stain with Congo red or thioflavin T. Immunofluorescency test usually shows the presence of IgG, namely the subclasses IgG4, C3 and kappa and lambda of light immunoglobulin chains. The presented case report describes clinical and laboratory findings at a patient suffering from nephrotic syndrome. Results of renal biopsy and detailed histological examinations concluded the diagnosis as fibrillary glomerulonephritis. The patient was treated with a combination of prednisone (1 mg/kg/24 hrs) with cyclophosphamide (2 mg/kg/24 hrs) for six months. This led to a decrease of proteinuria from the initial value of 5.38 g/24 hours to 1.88 g/24 hours, as well as to a partial remission of nephritic syndrome. Glomerular filtration, evaluated using endogenous creatinine clearance, remained within limits of normal values throughout the follow-up, with the value of 2.6 ml/s after the treatment.

Intraembryonic avian leukosis virus subgroup C (ALV-C) inoculation producing wasting disease in ducks soon after hatching

We have studied the pathogenic changes in Khaki Campbell ducks injected in mid embryogenesis with ALV subgroup C virus td daPR-C derived from a molecular clone. The employed duck flock was shown to be highly genetically homogeneous and was controlled for the absence of current infections. Clear symptoms of wasting disease, which appeared since one week post hatching, represented the early consequence of the virus infection. They were manifested by decreased body weight, including clear involution of thymic tissue and pronounced anaemia. Microscopically, thymuses of infected animals displayed lymphatic depletion, clearly visible in the lobular cortex. Similarly, in the bursa Fabricii follicles, a marked reduction of the cortical layer and a decrease in folicullar centres was revealed. A decrease in the antibody response correlated with bursa Fabricii atrophy. The clear signs of anaemia were confirmed by haematological measurements, red blood cell count, haematocrit value and haemoglobin included. On the basis of these and additional observations we propose that inoculation of duck embryos provides a suitable model for analysis of the wasting disease produced by ALV-C.

Chronic endothelin receptor blockade reduces end-organ damage independently of blood pressure effects in salt-loaded heterozygous Ren-2 transgenic rats

The present study was performed to evaluate the role of an interaction between the endothelin (ET) and the renin-angiotensin systems (RAS) in the development and maintenance of hypertension and in hypertension-associated end-organ damage in heterozygous male and female transgenic rats harboring the mouse Ren-2 renin gene (TGR). Twenty-eight days old heterozygous TGR and age-matched transgene-negative normotensive Hannover Sprague-Dawley rats (HanSD) were randomly assigned to groups with normal-salt (NS) or high-salt (HS) intake. Nonselective ET(A)/ET(B) receptor blockade was achieved with bosentan (100 mg.kg(-1).day(-1)). All male and female HanSD as well as heterozygous TGR on NS exhibited 100 % survival rate until 180 days of age (end of experiment). HS diet in heterozygous TGR induced a transition from benign to malignant phase hypertension. The survival rates in male and in female heterozygous TGR on the HS diet were 46 % and 80 %, respectively, and were significantly improved by administration of bosentan to 76 % and 97 %, respectively. Treatment with bosentan did not influence either the course of hypertension (measured by plethysmography in conscious animals) or the final levels of blood pressure (measured by a direct method in anesthetized rats) in any of the experimental groups of HanSD or TGR. Administration of bosentan in heterozygous TGR fed the HS diet markedly reduced proteinuria, glomerulosclerosis and attenuated the development of cardiac hypertrophy compared with untreated TGR. Our data show that the ET receptor blockade markedly improves the survival rate and ameliorates end-organ damage in heterozygous TGR exposed to HS diet. These findings indicate that the interaction between the RAS and ET systems plays an important role in the development of hypertension-associated end-organ damage in TGR exposed to salt-loading.

[Renal infiltration in lymphoma--diagnosis in renal biopsy (case report)]

A case story of a patient with renal biopsy (RB) proven infiltration with lymphoma is given. RB in patient with known malignancy and onset of renal failure was indicated with regard to an atypical picture of kidney involvement (non-enlarged kidneys, without any structural changes typical for tumour mass presence). Though spread of the primary tumour to the kidney is not uncommon, involvement severe enough to impair renal function is unusual and occurs primarily with rapidly growing haematologic malignancies; diagnosis is being established by renal biopsy only rarely.

[Invagination--the first manifestation of leiomyosarcoma]

The authors describe in their paper one of the less frequent ileus acute abdominal events in adult age--invagination. At the same time they comment also on the rare cause of invagination, a leiomyosarcoma of the small intestine. In the discussion they mention the relationship of this tumour to gastrointestinal stromal tumours.

Influence of losartan and enalapril on urinary excretion of 8-isoprostane in experimental nephrotic syndrome

BACKGROUND

The increased permeability of the glomerular capillary wall in adriamycin nephropathy may be mediated by increased generation of free radicals, possibly also by the non-enzymatic production of isoprostanes induced by oxidative stress. ACE inhibitors and angiotensin II antagonists may reduce proteinuria, perhaps by decreasing intraglomerular pressure and increasing the selective permeabiity of the glomerular capillary wall.

MATERIAL/METHODS

We compared the effect of an ACE inhibitor, enalapril, and an angiotensin II antagonist, losartan, on total malodialdehyde in blood and the urinary excretion of certain eicosanoids and their metabolites (TxB(2), 6-keto-PGF(1alpha), bicyclo-PGE(2) and 8-isoprostane) in experimental adriamycin-induced nephrotic syndrome in rats.

RESULTS

Increased proteinuria in adriamycin-treated rats was not prevented by losartan, but tended to be partly mitigated by enalapril. However, both losartan and enalapril prevented the adriamycin-induced increase of total MDA in serum, but urinary excretion of 8-isoprostane was increased in nephrotic rats treated by losartan compared to controls. The enalapril-induced increase in urinary excretion of bicyclo-PGE(2) was possibly mediated by kinins. Proteinuria positively correlated with urinary excretion of 8-isoprostane, and proteinuric rats also had a significantly higher urinary excretion of 8-isoprostane than non-proteinuric rats.

CONCLUSIONS

Proteinuria in the acute phase of adriamycine nephropathy may be dependent on free radical generation and the formation of 8-isoprostane. The mild antiproteinuric effect of enalapril, but not losartan, may suggest the contributory role of the inhibition of kinin degradation in the antiproteinuric action of enalapril in this model of nephrotic syndrome.

[Kidney involvement in light-chain deposition disease]

An overview concerning different types of kidney involvement associated with monoclonal gammapathy (MG) is given, focused on light-chain deposition disease (LCDD). Pathophysiologic basis of LCDD remains in the light-chain tissue deposition (resp. in tissue deposition of immunoglobulin's stable domain). This mechanism is typical for monoclonal immunoglobulin's overproduction as found in MG. Clinical picture of LCDD reflects multiorgan character of disorder, while renal lesions rank among the most frequent, serious and best documented ones. Clinical data referring to a group of six patients, treated in our nephrologic department are presented. Diagnosis of LCDD was established on basis of the renal biopsy finding. Renal functions were decreased at the time of diagnosis in all patients, whereas haemodialysis treatment was started in one patient. On conclusion therapeutic possibilities of LCDD are discussed, in which number symptomatic therapy of renal failure is combined with corticosteroids therapy and cytostatic therapy; prognosis of most patients remains serious.

[Multiple extrarenal complications in Wegener granulomatosis]

This is a case report of a patient with Wegener's granulomatosis (WG), who initially presented with a corneal perforation. In addition to the eye involvement, the pauciimmune necrotizing glomerulonephritis with crescent formation, E.N.T. and pulmonary involvement were diagnosed. The patient also suffered from the acute myocardial infarction, most likely due to coronal arteritis. In addition to the coronal ischaemia she also had vasculitis of the aortic valve due to the WG. Another rare complication was the massive intestinal bleeding. The patient had also a skin vasculitis and non-specific symptoms such as artralgias and fever. The correct diagnosis was supported by positive cANCA. A clinical and laboratory remission of the disease was achieved by combined immunosuppressive therapy. Subsequently, she developed a subglotic stenosis possibly due to reparative changes.

Retroviruses in foreign species and the problem of provirus silencing

Retroviruses are known to integrate in the host cell genome as proviruses, and therefore they are prone to cell-mediated control at the transcriptional and posttranscriptional levels. This plays an important role especially after retrovirus heterotransmission to foreign species, but also to differentiated cells. In addition to host cell-mediated blocks in provirus expression, also so far undefined host specificities, deciding upon the pathogenic manifestation of retrovirus heterotransmission, are in play. In this respect, we discuss especially the occurrence of wasting disease and immunodeficiency syndrome, which we established also in avian species using avian leukosis virus subgroup C (ALV-C) inoculated in mid-embryogenesis in duck or chicken embryos. The problem of provirus downregulation in foreign species or in differentiated cells has been in the recent years approached experimentally. From a series of observations it became apparent that provirus downregulation is mediated by its methylation, especially in the region of proviral enhancer-promoter located in long terminal repeats (LTR). Several strategies have been devised in order to protect the provirus from methylation using LTR modification and/or introducing in the LTR sequence motifs acting as antimethylation tags. In such a way the expression of retroviruses and vectors in foreign species, as well as in differentiated cells, has been significantly improved. The complexity of the mechanisms involved in provirus downregulation and further possibilities to modulate it are discussed.

[Occurrence of reflux esophagitis in patients with chest pain and a normal selective coronary angiogram]

BACKGROUND

Chest pains are related to coronary disease, and to several other disorders, among which the most commons are the oesophageal diseases. The aim of the work was the identification of the reflux oesophagitis in patients with chest pain and normal selective coronary angiogram.

METHODS AND RESULTS

In the examined group 65 patients (42 females, 23 males) of the average age 55.2 years were included. All of them underwent endoscopic investigation with biopsy from the terminal part of the oesophagus. Endoscopy picture was evaluated according Savary-Miller classification. Biopsy samples were histologically examined and evaluated according our proper classification of the reflux oesophagitis (1st degree: mild, 2nd degree: medium, 3rd degree: heavy, 4th degree: ulcerous). Endoscopical finding was normal in 59 patients (90.8%), reflux oesophagitis of the 1st degree in 2 patients (3.1%) 2nd degree in one patient (1.5%), 3rd degree in 2 patients (3.1%), 4th degree in one patient (1.5%). Histological changes which can be included into the picture of so called microscopic oesophagitis were found in 49 patients (75.4%). The rest of patients had the histology picture normal.

CONCLUSION

In 75.4% of patients with chest pain and negative selective coronary angiogram histological examination revealed structural changes corresponding with oesophagitis, mostly of the mild type.

Proviral load and expression of avian leukosis viruses of subgroup C in long-term persistently infected heterologous hosts (ducks)

Proviral DNA load and expression of avian leukosis viruses of subgroup C (ALV-C) in ducks infected in mid embryogenesis were studied using quantitative PCR, RT-PCR, in situ hybridization employing ALV-specific riboprobe, and immunohistochemistry. A group of long-term surviving, non-reviremic ducks was selected for the study and compared to control reviremic animals in order to obtain information about persisting retroviruses in different duck tissues. A widespread distribution of proviruses in the tested tissues was found, but the proviral load was significantly lower in non-reviremic in comparison to reviremic animals. The only exception were brain and blood cells, in which no significant difference in the quantity of integrated proviruses was found between both categories of ducks, thus indicating an exceptional position of the brain and blood cells among all tested tissues. Contrary to reviremic, the proviruses were not transcribed in non-reviremic ducks, with the exception of brain and thymus. In the majority of non-reviremic ducks viral RNA was revealed in the brain, but no infectious virus could be recovered from this tissue. The opposite situation was observed in the thymus, where infectious virus was recovered but viral RNA remained below the detection limit of the assay. As revealed by in situ analysis, infected cells were either disseminated or focally distributed in tissues. From the long-term follow up of ALV-C in intraembryonally infected ducks we conclude that this model is suitable for the study of retrovirus persistence accompained both by the presence and absence of reviremias. The possible consequences of transmission and long-term persistence of retroviruses in the heterologous host for retroviral evolution are discussed.

[Effect of losartan and enalapril on urinary excretion of 8-isoprostane in experimental nephrotic syndrome]

BACKGROUND

Increased permeability of glomerular capillary wall in adriamycin nephropathy may be mediated by increased generation of free radicals and possibly also by the non-enzymatic production of isoprostanes induced by oxidative stress. ACE inhibitors may reduce proteinuria, possibly due to the decrease of intraglomerular pressure and increased permselectivity of the glomerular capillary wall. These effects may be partly mediated by the inhibition of the degradation of kinins. It is not clear if newly available angiotensin II antagonists have the same antiproteinuric and renoprotective effects.

METHODS AND RESULTS

We compared the effect of an ACE inhibitor (enalapril, 0.4 mg/kg bw i.p. daily for 3 weeks) and angiotensin II antagonist (losartan, 2 mg/kg bw in the same way) on experimental nephrotic syndrome induced in rats by the administration of adriamycin (5 mg/kg bw i.v. in a single dose). To elucidate the potential differences between these two drugs we also measured total malondialdehyde in blood and urinary excretion some eicosanoids and their metabolites (TxB2, 6-keto-PGF1alfa, bicyclo-PGE2 and 8-isoprostane). Proteinuria increased in adriamycin treated rats after 3 weeks from 0.18 +/- 0.01 to 0.44 +/- 0.14 g/mmol creat, p < 0.01. This increase was not prevented by losartan (increase from 0.18 +/- 0.12 to 0.50 +/- 0.11 g/mmol creat, p < 0.05), but tended to be partly blunted by enalapril (increase from 0.20 +/- 0.10 to only 0.32 +/- 0.08 g/mmol creat, p < 0.05). Similarly there was no increase of serum cholesterol, only in enalapril treated rats. On the other hand, both losartan (1.27 +/- 0.13 vs. 1.91 +/- 0.30 mumol/l, p < 0.05) and enalapril (0.93 +/- 0.06 mumol/l, p < 0.001) prevented adriamycin induced increase of total MDA in serum, but urinary excretion of 8-isoprostane was increased in nephrotic rats treated by losartan compared to controls. Enalapril induced increase of urinary excretion of bicyclo-PGE2 (4.32 +/- 0.62 vs. 1.66 +/- 0.81 ng/mmol creat, p < 0.001) was possibly mediated by kinins. There was no significant difference in the urinary excretion of other eicosanoids between different groups, but proteinuria correlated positively with urinary excretion of 8-isoprostane (p < 0.01). Proteinuric rats had also significantly higher urinary excretion of 8-isoprostane than non-proteinuric rats (44.8 +/- 7.1 vs. 26.7 +/- 3.4 ng/mmol. creat, p < 0.05).

CONCLUSIONS

Our data suggest that proteinuria in adriamycin nephropathy may mainly depend on free radical generation and the formation of 8-isoprostane. Haemodynamic parameters (glomerular pressure) do not seem to be so important. The mild antiproteinuric effect of enalapril may suggest a contributory role of the inhibition of kinin degradation in this model of nephrotic syndrome.

[A bizarre inflammatory polyposis of the colon in chronic ulcerative proctocolitis]

A case report of a young patient (born in 1980) with a 2-year history of chronic ulcerative proctocolitis was described. Checking colonoscopy 6 months from the beginning of disease showed multiple and even confluent polypoid lesions in transverse gut starting from hepatic flexure in addition to diffuse inflammatory rectosigmoideal changes. Biopsy found only colic mucosa without any tumorous structures. Five months later the patient's state got worse accompanied instantly by vomiting, weight loss and malabsorption symptoms. A duodenocolic fistula was supposed according to gastroduodenoscopy and biopsy. Because of progressive suffering of the patient colectomy with ileoduodenoanastomosis and ileosigmoidoanastomosis was performed. Polypous lesions were observed from the blind gut up to descendent colon and a transversoduodenal fistula was proved. The removed part of gut was completely changed into a dense network of elongated polypous lesions. In microscopy, bigger polyps showed an inner stromal part often with bands of smooth muscle cells covered by nearly normal gut mucosa. Smaller polyps were formed by hypertrophic gut mucosa only. At the base of polyps, a stagnation of gut contents was found as well as ulcerous defects of various depth. Macroscopy and microscopy of polypoid lesions formed by non-neoplastic gut mucosa were those of so called bizzare ("giant") inflammatory polyposis of the gut. Up to now the patient's clinical picture and local finding in the stump of resected gut have been typical for chronic ulcerous colitis and polypous lesions were not revealed by checking investigations.

[Laboratory findings and serum levels of amyloid A and soluble interleukin-2 receptors in patients with renal amyloidosis]

BACKGROUND

Renal amyloid involvement results either from primary or secondary amyloidosis. Extent of amyloid tissue deposition in kidneys and clinical course depends not only on the type of basic process but reflects also time of diagnosis and possibility to influence the basic process.

METHODS AND RESULTS

We analyzed laboratory and clinical data of patients with bioptically proven renal amyloidosis. We found renal amyloidosis in 27 patients from an overall number of 750 renal biopsies (RB) performed in our department (i.e. 3.6%). AA amyloidosis was diagnosed in 16 pts, AL amyloidosis in 11 pts. About 50% of patients had laboratory signs of nephrotic syndrome, all patients had various degree of proteinuria. Impaired renal function were found in more than 50% of patients, in 6 of them we had to start renal replacement therapy. 8 pts died. Complications of severe nephrotic syndrome were the causes of death in majority of cases. We have started investigation of some amyloid precursors and cytokines in patients with AA and AL amyloidosis. We compared the results with group of patients with vasculitis. We investigated plasma and urinary levels of SAA (serum AA) and soluble receptor for interleukin 2 (sIL-2R).

CONCLUSIONS

Clinical features and laboratory findings in our patients with renal amyloidosis approximately are in accordance with literary data. Plasmatic level of SAA was increased not only in the group of patients with AA amyloidosis, but also in the group of vasculitis. Urinary sIL-2R was significantly increased in patients with AA amyloidosis in comparison with healthy controls.

[Aggressive papillary adenoma of a digit]

A case of a rare skin adnexal tumour, aggressive digital papillary adenoma was described. The tumour had a characteristic forefinger localization, showed microscopical cystopapillary pattern combined with more solid and partly cribriform structures. Tumour cells were represented by lighter cuboid and darker smaller spindle elements. In immunohistology, the tumour cells were positive for epithelial markers (CK, EMA), minority of them showed S 100 protein positivity. Basal cells along the collagenous stroma tissue were strongly actin positive. The light microscopical picture was complemented by electron microscopy for the sake of a more detailed description of tumour cells.

[Lectins in pulmonary adenocarcinomas]

A relatively specific binding of lectins to various glycids enabled authors to evaluate the exosecretion characteristic of lung carcinomas closer than by HE, investigation of mucins and immunohistochemical epithelial markers. The main subtypes of lung adenocarcinomas (usual of acinar, tubulopillary cubocellular or cylindrocellular, solid with mucus production), pseudosarcoma, large cell and undifferentiated carcinomas from 9 bioptical samples were therefore compared as to binding of 5 lectins with preferential affinity to glucose/mannose (CON A), acetylglucosamin (WGA) and acetylgalactosamin (PNA, RCA, HPA). All the subtypes of adenocarcinoma as well as undifferentiated carcinoma showed a strong binding of bean lectin (CON A) and a slighter binding of ricinus (RCA) and wheat germ (WGA) lectins. Binding of Helix pomatia lectin (HPA) was nearly parallel to that of CON A even in large cell carcinoma (without mucin positivity)-except in undifferentiated carcinoma (in HE reminding of squamous carcinoma but CK negative). Peanut lectin (PNA) binding correlated with the production of acid glycosaminglycans and its lacking might serve as an indirect sign of Clara cell origin in some cubocellular bronchioloalveolar carcinomas which was otherwise difficult to prove. Lections mostly did not bind to mucus vacuoles and cytoplasmic granulary positivities represented secretion granules; marginal membranous positivities represented glycocalyx or lipoproteinaceous layer released by Clara cells in accordance with the expression of EMA. In pseudosarcoma a gradual binding of CON A from sarcomatoid to epithelial areas allowed to evaluate their connection better than according to an expression of cytokreatin.

Involution of the Wolffian duct in the rat

The involution of Wolffian duct in female rat fetuses from 15 to 21 days of gestation was studied in electron microscope. The female Wolffian duct stopped its differentiation on day 17 and the onset of duct regression was found in 18 days old fetuses. The involution was accompanied by degeneration and disintegration of epithelial cells, removal of basal lamina and elimination of altered cells into periductal mesenchyme. Although the mechanism of programmed cell death contributed to the WD regression the findings of non-altered epithelial cells supported the opinion of possible migration of some WD cells into the mesenchymal cell compartment.